well, I'll tell ya---if you try to be a dillatante and only dip in your toes without out an adequate investment, then the tools you have will be inadequate and it will not be a good experience.
however if you bite the bullet and buy the proper equipment up front--that INCLUDES a sufficient number of film holders--that will be your #1 thing to get in my opinion--11x14 portraits you will need to have a lot of these--don't expect every shot to go as planned or at all.
don't bother trying to build anything till you use some equipment for a while and you KNOW what you're doing. Things on a 4x5 or 8x10 are different on 11x14...the priorities change for what you want in a camera--I find I'm better off with more than one camera--each one suited to a specific task rather than buying an "all in one" camera---the all in one's try to add too much functionaliy and sacrifice rigidity and weight...however, that is all there is on the market---so buy one of them and you'll see what each type of shooting requires and allow sufficient knowledge to build your own cameras. THEN you can sell the original camera, probably for what you paid for it and you'll still keep your film holders...or you can sell the lot for what you paid likely...it's not like you'll be out any money on the deal---and TIME--it is more valuable than money--so just jump in or you'll be wondering "what if" you're whole life.